Portable folding chair

Abstract

A portable folding chair that is provided with a pair of telescoping side mounting members each made up of an inner and outer telescoping tube that are prevented from having sliding movement relative to each other when the chair is in its erected state, in order to stabilize the chair when sat upon. The outer tube constitutes the upper tube so that any sand or dirt entering into the interior of the telescoping members will fall right out again. The front support legs are sloped forwardly to allow for the chair to be more fully collapsed.

What I claim: 
     
       1. In a portable foldable chair comprising a seat, a seat-back structure, a supporting structure for supporting said seat on a surface, and arm-rest means also supported by said supporting structure, said arm-rest means comprising a pair of arms connected to said seat-back structure and a pair of adjustment-brackets mounted to the undersurfaces of said pair of arms by which said seat-back structure may be angularly adjusted, one said adjustment bracket for one said arm; said supporting structure comprising a front, U-shaped tubular assembly, a rear, U-shaped tubular assembly, and a pair of telescoping members, each said telescoping member being associated with one side of each front and rear U-shaped tubular assemblies; each said telescoping member comprising an upper end operatively associated with one said adjustment bracket for providing structural support and for allowing the chair to be folded and a lower end pivotally connected by means of a pivot pin to a respective portion of said supporting structure at an elevation lower than said adjustment bracket so that said telescoping member extends at an angle when the chair is erected; each said telescoping member comprising an outer telescoping tube and an inner telescoping tube slidable in said outer telescoping tube, one of said outer and inner telescoping tubes being an upper one, and the other of said outer and inner telescoping tubes being a lower one, said outer and inner tubes forming an annular gap therebetween, wherein the improvement comprises: said outer telescoping tube of each said telescoping member being the upper one and having said upper end operatively associated with a respective said adjustment bracket, and said inner telescoping tube of each said telescoping member being the lower one and having said lower end pivotally connected to a respective said portion of said rear, U-shaped tubular assembly, whereby sand and other particles entering into the interior of the telescoping member will fall out therefrom through the annular gap between the inner and outer telescoping tubes.   
     
     
       2. The chair according to claim 1, wherein said rear U-shaped tubular assembly is located at the rear of the chair, and comprises a pair of upper ends, each said upper end being pivotally connected to said lower end of a respective said telescoping member; each said upper end being sandwiched between the respective said lower end of said telescoping member and a respective said portion of said supporting structure; said pivot pin pivotally mounting said lower end of said telescoping member, said upper end of said rear U-shaped tubular assembly, and said portion of said supporting structure, whereby said pivot pin is strengthened and said supporting structure is stabilized. 
     
     
       3. The chair according to claim 1, further comprising a shoulder strap assembly comprising a shoulder strap having a free extensible end, a housing mounted to a first section of the chair for storing said shoulder strap therein in a rolled-up manner, and a receptor mounted to a second section of the chair for receiving said free end therein when said free end is extended from the housing to unwind the shoulder strap from the housing, said receptor latching said free end therein, whereby the chair may be carried by said strap after the chair has been folded and collapsed. 
     
     
       4. The chair according to claim 1 wherein each said telescoping member further comprises detent means for preventing said inner and outer telescoping tubes from moving relative to each other when the chair is in its erected state. 
     
     
       5. The chair according to claim 4, wherein each said detent means comprises a biassed pin, each of said inner and outer telescoping tubes having a through-hole through which said pin may pass when said holes are in alignment for preventing sliding movement therebetween. 
     
     
       6. The chair according to claim 5, wherein each said detent means comprises a U-shaped spring having a fixed end mounted to an interior portion of a respective said inner telescoping tube, and a free end; said pin being mounted to said free end of said U-shaped spring, whereby said U-shaped spring biases said pin outwardly through both said holes when said holes are in linear alignment. 
     
     
       7. The chair according to claim 4, wherein said front U-shaped tubular assembly comprises a pair of spaced-apart, approximately upright, forwardly-sloping tubular members each having an upper end pivotally connected to said upper end of a respective said upper telescoping tube, a respective said adjustment bracket being sandwiched therebetween. 
     
     
       8. In a portable foldable chair comprising a seat, and a supporting structure for supporting said seat on a surface, said supporting structure comprising a front, U-shaped tubular assembly, a rear, U-shaped tubular assembly, and a pair of telescoping members, each said telescoping member being associated with one side of each of said front and rear U-shaped tubular assemblies; each said telescoping member comprising an upper end operatively associated with an upper section of said front U-shaped tubular assembly, and a lower end pivotally connected by means of a pivot pin to a respective portion of said supporting structure at an elevation lower than an adjustment bracket so that said telescoping member extends at an angle when the chair is erected; each said telescoping member comprising an outer telescoping tube and an inner telescoping tube slidable in said outer telescoping tube, one of said outer and inner telescoping tubes being an upper one, and the other of said outer and inner telescoping tubes being a lower one, said outer and inner tubes forming an annular gap therebetween, wherein the improvement comprises: said outer telescoping tube of each said telescoping member being the upper one and having said upper end operatively associated with a respective said upper section of said front U-shaped tubular assembly, and said inner telescoping tube of each said telescoping member being said lower one and having a lower end pivotally connected to a respective said portion of said rear, U-shaped tubular assembly, whereby sand and other particles entering into the interior of the telescoping member will fall out therefrom through the annular gap between the inner and outer telescoping tubes.   
     
     
       9. The chair according to claim 8, wherein said rear U-shaped tubular assembly is located at the rear of the chair, and comprises a pair of upper ends, each said upper end being pivotally connected to said lower end of a respective said telescoping member; each said upper end being sandwiched between the respective said lower end of said telescoping member and a respective said portion of said supporting structure; said pivot pin pivotally mounting said lower end of said telescoping member, said upper end of said rear U-shaped tubular assembly, and said portion of said supporting structure, whereby said pivot pin is strengthened and said supporting structure is stabilized. 
     
     
       10. The chair according to claim 8, wherein each said telescoping member further comprises detent means for preventing said inner and outer telescoping tubes from moving relative to each other when the chair is in its erected state. 
     
     
       11. The chair according to claim 10, wherein each said detent means comprises a biassed pin, each of said inner and outer telescoping tubes having a through-hole through which said pin may pass when said holes are in alignment for preventing sliding movement therebetween. 
     
     
       12. The chair according to claim 11, wherein each said detent means comprises a U-shaped spring having a fixed end mounted to an interior portion of a respective said inner telescoping tube, and a free end; said pin being mounted to said free end of said U-shaped spring, whereby said U-shaped spring biases said pin outwardly through both said holes when said holes are in linear alignment. 
     
     
       13. The chair according to claim 10, wherein said front U-shaped tubular assembly comprises a pair of spaced-apart, approximately upright, forwardly-sloping tubular members each having an upper end pivotally connected to said upper end of a respective said upper telescoping tube, a respective said adjustment bracket being sandwiched therebetween. 
     
     
       14. In a portable foldable chair comprising a seat, and a supporting structure for supporting said seat on a surface, said supporting structure comprising a front, U-shaped tubular assembly, a rear, U-shaped tubular assembly, and a pair of telescoping members, each said telescoping member being associated with one side of each of said front and rear U-shaped tubular assemblies; each said telescoping member comprising an upper end operatively associated with an upper section of said front U-shaped tubular assembly, and a lower end pivotally connected by means of a pivot pin to a respective portion of said supporting structure at an elevation lower than an adjustment bracket so that said telescoping member extends at an angle when the chair is erected; each said telescoping member comprising an outer telescoping tube and an inner telescoping tube slidable in said outer telescoping tube, wherein the improvement comprises: each said telescoping member comprising detent means for preventing said inner and outer telescoping tubes from moving relative to each other when the chair is in its erected state;   each said detent means comprising a biased pin, each of said inner and outer telescoping tubes having a through-hole through which said pin may pass when said holes are in alignment for preventing the sliding movement therebetween; and   each said detent means also comprising a U-shaped spring having a fixed end mounted to an interior portion of a respective said inner telescoping tube, and a free end; said pin being mounted to said free end of said U-shaped spring, whereby said U-shaped spring biases said pin outwardly through both said holes when said holes are in linear alignment.   
     
     
       15. The chair according to claim 14, wherein said front U-shaped tubular assembly comprises a pair of spaced-apart, approximately upright, forwardly-sloping tubular members each having an upper end pivotally connected to said upper end of a respective said telescoping member, a respective said adjustment bracket being sandwiched therebetween. 
     
     
       16. The chair according to claim 15, wherein each of said pair of spaced-apart, approximately upright, forwardly-sloping tubular members makes an acute angle of approximately between 5 and 15 degrees with respect to a vertical plane. 
     
     
       17. The chair according to claim 14, further comprising a shoulder strap assembly comprising a shoulder strap having a free extensible end, a housing mounted to a first section of the chair for storing said shoulder strap therein in a rolled-up manner, and a receptor mounted to a second section of the chair for receiving said free end therein when said free end is extended from the housing to unwind the shoulder strap from the housing, said receptor latching said free end therein, whereby the chair may be carried by said shoulder strap after the chair has been folded and collapsed. 
     
     
       18. The chair according to claim 17, wherein said housing is mounted to a lower exterior portion of said rear U-shaped tubular assembly; said receptor being mounted to an exterior portion of one of said telescoping members located above said lower exterior portion of said U-shaped tubular assembly. 
     
     
       19. In a portable foldable chair comprising a seat, a supporting structure for supporting said seat on a surface, a pair of arm-rests, and a base upon which said supporting structure is mounted; said supporting structure comprising a front, U-shaped tubular assembly, and a rear, U-shaped tubular assembly, and a plurality of clamps for rotatably mounting said supporting structure to said base, said plurality of clamps fixedly connecting the lower horizontal tubes of said front and rear U-shaped tubular assemblies to said base, wherein the improvement comprises: said lower horizontal tube of said rear U-shaped tubular assembly comprising a plurality of upwardly projecting limit stops; each said clamp operatively associated with said lower horizontal tube of said rear U-shaped tubular assembly lying laterally interiorly of at least one said limit stop, whereby said limit stops prevent said lower horizontal tubes of said front and rear U-shaped tubular assemblies from sliding relative to said clamps.   
     
     
       20. In a portable foldable chair comprising a seat, and a supporting structure for supporting said seat on a surface, said supporting structure comprising a front, U-shaped tubular assembly, a rear, U-shaped tubular assembly, and a pair of telescoping members, each said telescoping member being associated with one side of each of said front and rear U-shaped tubular assemblies; each said telescoping member comprising an upper end operatively associated with an upper section of said front U-shaped tubular assembly, and a lower end pivotally connected by means of a pivot pin to a respective portion of said supporting structure at an elevation lower than said adjustment bracket so that said telescoping member extends at an angle when the chair is erected; each said telescoping member comprising an outer telescoping tube and an inner telescoping tube slidable in said outer telescoping tube, wherein the improvement comprises: said rear U-shaped tubular assembly being located at the rear of the chair, and comprises a pair of upper ends, each said upper end being pivotally connected to said lower end of a respective said telescoping member; each said upper end being sandwiched between the respective said lower end of said telescoping member and a respective said portion of said supporting structure; said pivot pin pivotally mounting said lower end of said telescoping member, said upper end of said rear U-shaped tubular assembly, and said portion of said supporting structure, whereby said pivot pin is strengthened and said supporting structure is stabilized.   
     
     
       21. In a portable foldable chair comprising a seat, and a supporting structure for supporting said seat on a surface, said supporting structure comprising a front, U-shaped tubular assembly, a rear, U-shaped tubular assembly, and a pair of telescoping members, each said telescoping member being associated with one side of each of said front and rear U-shaped tubular assemblies; each said telescoping member comprising an upper end operatively associated with an upper section of said front U-shaped tubular assembly, and a lower end pivotally connected by means of a pivot pin to a respective portion of said supporting structure at an elevation lower than an adjustment bracket so that said telescoping member extends at an angle when the chair is erected; each said telescoping member comprising an outer telescoping tube and an inner telescoping tube slidable in said outer telescoping tube, wherein the improvement comprises: each said telescoping member comprising detent means for preventing said inner and outer telescoping tubes from moving relative to each other when the chair is in its erected state;   said front U-shaped tubular assembly comprising a pair of spaced-apart, approximately upright, forwardly-sloping tubular members each having an upper end pivotally connected to said upper end of a respective said upper telescoping tube, a respective said adjustment bracket being sandwiched therebetween.   
     
     
       22. The chair according to claim 21, wherein each of said pair of spaced-apart, approximately upright, forwardly-sloping tubular members makes an acute angle of approximately between 5 and 15 degrees with respect to a vertical plane. 
     
     
       23. In a portable foldable chair comprising a seat, and a supporting structure for supporting said seat on a surface, the improvement comprising: a shoulder strap assembly comprising a shoulder strap having a free extensible end, a housing mounted to a first section of the chair for storing said shoulder strap therein in a rolled-up manner, and a receptor mounted to a second section of the chair for receiving said free end therein when said free end is extended from the housing to unwind the shoulder strap from the housing, said receptor latching said free end therein, whereby the chair may be carried by said shoulder strap after the chair has been folded and collapsed.   
     
     
       24. The chair according to claim 23, wherein said supporting structure comprises a front, U-shaped tubular assembly, a rear, U-shaped tubular assembly, and a pair of telescoping members, each said telescoping member being associated with one side of each of said front and rear U-shaped tubular assemblies; each said telescoping member comprising an upper end operatively associated with an upper section of said front U-shaped tubular assembly, and a lower end pivotally connected by means of a pivot pin to a respective portion of said supporting structure at an elevation lower than an adjustment bracket so that said telescoping member extends at an angle when the chair is erected; each said telescoping member comprising an outer telescoping tube and an inner telescoping tube slidable in said outer telescoping tube; said housing being mounted to a lower exterior portion of said rear U-shaped tubular assembly; said receptor being mounted to an exterior portion of one of said telescoping members located above said lower exterior portion of said U-shaped tubular assembly.